Surgery plays a prominent role in healthcare worldwide. It has been
estimated that the rate of fatal events occurring in surgery is about
one in ten thousand exposures and up to one million deaths per year.
Most errors are caused by failure of non-technical skills. The WHO
surgical safety checklist has shown that patient safety could be
improved by using a simple and effective method. However, achieving high
compliance requires research, training and local adaptation.

The delivery of healthcare is complex, with potential for errors
caused by human factors and system failures (Panesar et al 2011). In the
twenty first century, patient safety has become an important issue in
healthcare management worldwide (Yang et al 2007). Most errors that
occur in surgery are caused by failures of non-technical skills such as
communication, leadership and teamwork. To increase awareness and
understanding of this considerable issue, patient safety is being
developed as a medical school curriculum by patient safety scholars in
partnership with John Hopkins University (Lancet editorial 2008).

Surgery plays a prominent role in healthcare worldwide with growing
attention to quality and safety in the delivery of such care (Haynes et
al 2011). The increasing focus on surgical safety appeared with the
categorisation of surgery as a very unsafe industry. It has been
estimated that 234 million operations are being carried out annually
worldwide with a rate of fatal events occurring at 1 per 10,000
exposures, and up to one million deaths per year (Haynes et al 2009).

Trauma surgery alone has a complication rate of 1 in 100 exposures,
whereas the rate of death in the aviation, railway and nuclear
industries is less than one per million exposures (Emerton et al 2009).
In developed countries, the rate of serious complications from surgical
procedures ranges from 3 to 16%, and interestingly, around half of these
incidents are preventable and avoidable (Lancet editorial 2008, Mahajan
2011, Allard et al 2011).

Evidence from root cause analyses suggests that we do most of the
things for most patients most of the time, but not all of the things for
all patients all the time (Reid & Clarke 2009) Although the
incidence of operating on the wrong patient or wrong site is rare, the
consequences are considerably harmful to the patient (Panesar et al
2009). In 2007 a surgical safety checklist was introduced globally
through the World Health Organization's Safe Surgery Saves Lives
program to reduce complications and deaths associated with surgery
(Haynes et al 2009).

Objective

This review looked into the historic events and the evidence behind
the introduction of the World Health Organization (WHO) checklist in
clinical practice, and the evidence following its implementation.

Methods

A critical appraisal of the WHO surgical safety checklist
publication by Haynes et al was carried out. A literature search was
performed to identify the relevant articles according to an agreed
search strategy and inclusion criteria. The relevant articles were
included in this review.

Search strategy

An electronic search of medical databases including Medline/Pubmed,
CINAHL and EMBASE was carried out. The keywords used were: surgical
safety, surgical checklist, WHO. To be included in the review identified
articles were: clinical studies, editorials or reviews published in
English between January 2009 and September 2011. The search resulted in
182 articles which were analysed by the authors. Seventeen of those 182
articles were considered to fulfil the inclusion criteria and were
included in this review.

Discussion

The WHO has been, and is still, considering safe surgery as a
significant public health concern in the developing and developed
countries (Schlack & Boermeester 2010). In 2007, the WHO initiated a
programme called Safe Surgery Saves Lives which was aimed at improving
safety in surgery on a global scale. The surgical safety checklist was
created in an attempt to address this concern (Haynes et al 2009,
Panesar et al 2011).

The origin of safety checklists perhaps lies in the aviation
industry (Emerton et al 2009). In an American Army flight competition
held in 1935, a highly technically gifted pilot flew a Boeing plane. The
plane lifted off and climbed to three hundred feet, stalled, turned on
one wing, and crashed in a fiery explosion. The pilot and another member
of the crew died. An investigation revealed no mechanical errors, but
the pilot had forgotten to release the new locking mechanism. A few
months later, army pilots invented a checklist with step-by-step checks
for takeoff, flight, landing, and taxiing. With the checklist in hand,
the pilots went on to fly a total of 1.8 million miles through several
conflicts without one accident reported (Gawande 2007).

This incident has been considered as the key milestone in the
development of safety checklists (Emerton et al 2009). Since then the
checklists, along with briefing and debriefing sessions, have become
instrumental in enhancing the safety culture (Mahajan 2011). The key
elements of safety checklists are certainly not new to surgeons or
anaesthetists, as information is routinely checked and documented. For
example, orthopaedic surgeons in North America have been encouraged to
prevent wrong-site surgery since 1997 following the recommendations by
the American Academy of Orthopaedic Surgeons and the Canadian
Orthopaedic Association (Yang et al 2007). The Royal College of Surgeons
of England recognised the obligation of surgeons to conduct preoperative
briefing as part of a responsibility to patient safety (Allard et al
2011). However, the medical profession in general has been criticised as
being slow in adopting safety checklists (Mahajan 2011).

The WHO surgical safety checklist

In 2007, a nineteen item checklist was developed by the WHO
Safe-Surgery-Saves-Lives group (WHO 2007), and it was introduced in
eight countries (Haynes et al 2009). The authors hypothesised that the
implementation of a surgical safety checklist together with changes in
culture would lead to a reduction in major surgical complications and
death rates after surgery in various healthcare settings. Eight
hospitals in eight countries with different socioeconomic environments
were selected to participate in the implementation of the checklist.
Since the publication of the Haynes study, 3900 hospitals in 122
different countries have adopted the use of the checklist, with national
level adoption in 25 countries (Conley et al 2011). All UK hospitals
implemented the check list in 2010 (Panesar et al 2011).

Data were collected prospectively to determine the baseline status
prior to implementation of the checklist, followed by prospective
collection of data following the introduction of the checklist. Training
was provided to the operating-room staff by the local study group and
data collectors.

The checklist consists of three safety checks and junctures:
'Sign in', 'Time out' and 'Sign out'. At
these junctures, all operating room team members should stop their
activities and pay attention to the check. The patients can also
participate in the 'Sign in' phase prior to induction of
anaesthesia to check identity and planned procedure (Haynes et al 2009).

* Sign in

Prior to induction of anaesthesia, members of the team orally
confirm that the patient has verified his or her identity, the surgical
site and procedure, and given consent. It also confirms whether the
surgical site is marked or that site marking is not applicable. In
addition, it confirms the pulse oximeter is on the patient and
functioning and whether all members of the team are aware of whether the
patient has a known allergy. The patient's airway and risk of
aspiration is evaluated and appropriate equipment and assistance are
available. If there is a risk of blood loss of at least 500 ml (or 7
ml/kg of body weight in children), appropriate access and fluids are
made available (Haynes et al 2009).

* Time out

Prior to skin incision, the entire team (nurses, surgeons,
anaesthesia professionals and any others participating in the care of
the patient) orally confirms that all team members have been introduced
by name and role, the patient's identity, surgical site, and
procedure. The surgeon reviews the anticipated and unexpected critical
events, operative duration, and anticipated blood loss. Anaesthesia
staff review concerns specific to the patient. Nursing staff review
confirmation of sterility, equipment availability, and other concerns.
Prophylactic antibiotics are administered within 60 minutes of the
incision or a clarification is made that antibiotics are not indicated.
All essential imaging results for the correct patient are checked if
displayed in the operating room (Haynes et al 2009).

* Sign out

Before the patient leaves the operating room, the nurse reviews
items aloud with the team, name of the procedure as recorded, and the
needle, sponge, and instrument counts. The nurse also confirms the
specimen (if any) is correctly labelled, including with the
patient's name and whether there are any issues with equipment to
be addressed. The surgeon, nurse, and anaesthesia professional review
aloud the key concerns for the recovery and care of the patient (Haynes
et al 2009).

Critical appraisal

The study asks a clear and focussed question about whether a
surgical safety checklist reduces the morbidity and mortality in a
global population. The authors claim that there was no statistically
significant difference between the two groups, but this only applies
according to the study to age, sex, urgency of case, whether it was an
outpatient procedure or not and whether general anaesthesia was used.
There is no evidence from the data presented as to whether the American
Society of Anaesthesiologists (ASA) grade of the patients, the surgical
specialty and/or patient co-morbidities were taken into consideration
when comparing both groups. This could have potentially influenced the
results of the study with regards to mortality if there was a
statistically significant difference in the ASA grade of the patients or
the patients' co-morbidities. A similar effect could have been
observed when adjusting for surgical speciality, for example:
orthopaedics, where the appropriate use of antibiotics could influence
the rate of infection (Haynes et al 2009).

A sample size was calculated with high statistical power (80%),
although this was not achieved in three sites even after the extension
of the study period, with no explanation on the implication of this on
the statistical power of the study. According to the study, local ethics
committees were approached to approve the study, who waived the
requirement to obtain patient consent. The only two exclusion criteria
mentioned in the published study were if patients were under the age of
16 years and/or if patients were undergoing cardiac surgery.

The outcomes of the study were clearly defined prior to the study
and had been fully followed up for the participating patients in each
site. The results were blinded to the primary investigators at the local
hospital by the data collectors.

The study showed that complication rates reduced from 11% to 7%
(p<0.001), and mortality rate was reduced from 1.5% to 0.8% (p=0.003)
with use of the checklist. The impact on mortality was predominantly
observed in data from the developing countries. In addition, the largest
reduction in surgical site infection (from 20.5% to 3.6%) was observed
in one of the resource-poor hospitals who had no policy of routine
antibiotic prophylaxis within 60 minutes prior to the implementation of
the checklist (Senior 2009). In contrast, there was no significant
difference in reduction of the mortality rate in hospitals of high
income countries, which makes it difficult to draw conclusions on the
effect on implementing the checklist in the UK (Vijayasekar & Steel
2009).

The introduction of the WHO surgical safety checklist is an
important step in introducing safe culture in surgery, and medicine in
general (Schlack & Boermeester 2010), with a unique opportunity for
clinicians to provide leadership (Mahajan 2011). It is equally important
that systems are in place to detect errors before they escalate and that
there is defensive capacity when events develop further (Panesar et al
2011).

This study has shown that the core set of the safety checks in the
WHO surgical safety checklist can be applied to any surgical setting
(Panesar et al 2011). It has also provided good evidence that routine
preoperative time-out procedures reduce postoperative mortality and
complications (Schlack & Boermeester 2010). The importance of
teamwork has been emphasised in this study, which could have directly or
indirectly contributed to the good outcomes. Taylor et al (2010)
acknowledged that communication and conversation between the team
members, not the exact documentation, create a healthy culture.
Moreover, communication failures result in errors in omission and
commission, and it is rational that team members should be communicating
respectfully and efficiently.

The adoption of the WHO surgical safety checklist has been met with
mixed reactions (Mahajan 2011). Despite the robust and strong evidence
provided by the study, it could not identify the exact mechanisms by
which these results were achieved (Schlack & Boermeester 2010). This
was acknowledged by Haynes et al (2011). The reasons were considered to
be multifactorial involving system changes, team behaviour factors and
communication. Interpretation of the study results should be approached
carefully, as extrapolation of the results in a total population of
around 8000 to a large world surgical population of 234 million is risky
(Taylor et al 2010).

Mahajan has highlighted a number of barriers to the implementation
of the WHO surgical safety checklist (Mahajan 2011). Bringing members of
the team face to face together could potentially cause embarrassment
especially in operating theatres where this procedure is an entirely new
concept and it may take time for staff to be familiarised with the
routine. Hierarchy of staff could also be a barrier in implementation,
and the checklist is more likely to be completed when the surgeons and
anaesthetists are supportive or when the nurses were confident. Also, it
is often difficult to have a surgeon present during the sign in and sign
out phases, when surgeons are either seeing other patients or writing
operation notes.

A safety checklist should be simple, as evidence from the nuclear
industry suggests that there may be higher chance in overlooking items
when the list grows (Mahajan 2011). Even with simple checklists,
adoption would efficiently occur after gaining the support of staff, as
efforts to push the implementation could potentially lead to the process
becoming a tick-box exercise without realisation of its benefits. This
view has been shared by other authors who considered that the addition
of a new checklist to the existing burden of tick-box lists without
appropriate training could lead to tick-box fatigue, and at worst could
turn out to be counter-productive (Vijayasekar & Steele 2009).
Panesar et al (2010) have also suggested that incorrect use of
checklists can be hazardous to patients, and could lead to prolonged
theatre lists.

Some of above barriers have been addressed by Conley et al (2011)
who suggested that sustaining success in implementation of the surgical
safety checklist is through ongoing observation, with emphasis on
reading the checklist rather than relying on memory They also concluded
that effectiveness of implementation relies on the ability to explain
why and how to use the checklist. Vijayasekar and Steele (2009)
concluded that no studies have yet examined team composition or
experience and its impact on outcomes, and it would be difficult to draw
conclusions on the mechanism of achieving such results with the
introduction of a safety checklist. They have also concluded that
without robust data collection systems set up to study the
implementation of this checklist, the clinical effectiveness lacks the
backing of sound clinical knowledge.

Recommendations

Patient safety has been and will always be a priority in any
healthcare setting. Use of the surgical safety checklist has shown good
evidence in reducing mortality and morbidity, and it has been suggested
that the list should be adapted to local circumstances due to
differences between surgical specialties. A multidisciplinary checklist
that covers the whole surgical pathway from admission to discharge is
encouraged (Schlack & Boermeester 2011). However, modifying for
local use may increase complexity and result in less functionality
(Wilson & Walker 2009). To achieve high levels of compliance,
vigorous procedures such as legislation are required (Yang et al 2007),
in addition to guidance by passionate leadership and execution by
committed staff (Taylor et al 2010). It is also reassuring that
compliance with checklist completion improves over time with integration
into the culture and workflow of the operating room (Avansino et al
2011).

In summary, The WHO surgical safety checklist has shown that
patient safety could be improved using a simple, effective and
affordable method. However, achieving high compliance and the presence
of various implementation barriers requires effort through research,
training and local adaptation.

Main messages

* Most errors that occur in surgery are caused by failures of
non-technical skills such as communication, leadership and teamwork.

* The WHO surgical safety checklist has shown that patient safety
can be improved using a simple, effective and affordable method.

* Achieving high compliance and the presence of various
implementation barriers requires effort through research, training and
local adaptation.

Panesar SS, Noble DJ, Mirza SB et al 2011 Can the surgical
checklist reduce the risk of wrong site surgery in orthopaedics? - can
the checklist help? Supporting evidence from analysis of a national
patient incident reporting system Journal of Orthopaedic Surgery and
Research 6 18